The analysis of AI Mode and AI Overviews reveals that, despite a high semantic similarity of 86%, the two systems draw from markedly different sources. Only 13.7% of citations overlap, indicating that they are not merely variations of the same response but distinct systems converging on similar conclusions through different sources. For marketers, this raises important questions about brand visibility and content strategy. If a brand appears in AI Overviews, it has a 61% chance of being mentioned in AI Mode, but the latter includes significantly more entities—about 2.5 times more than the former. On the technical side, the study analyzed 730,000 response pairs, measuring citation patterns, content similarity, and entity mentions. The word-level overlap is a mere 16%, with identical first sentences appearing in only 2.51% of cases. This suggests that both systems generate their responses independently. The analysis also indicates that AI Mode tends to lean towards more encyclopedic and detailed sources, while AI Overviews favor video content and community-driven platforms like Reddit. For instance, YouTube is the top cited source in AI Overviews, whereas Wikipedia appears more frequently in AI Mode. The differences in content length are striking; AI Mode responses are roughly four times longer than AI Overviews. While AI Overviews mention brands selectively, AI Mode adds several brand mentions throughout the response. This means that if your brand is cited in AI Overviews, it may appear in AI Mode but alongside additional competitors. The findings highlight the need for tailored optimization strategies for each system due to their distinct citation practices and content styles.